package cn.agile4j.rpc.utils;


import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

import org.objenesis.Objenesis;
import org.objenesis.ObjenesisStd;

import com.dyuproject.protostuff.LinkedBuffer;
import com.dyuproject.protostuff.ProtobufIOUtil;
import com.dyuproject.protostuff.Schema;
import com.dyuproject.protostuff.runtime.RuntimeSchema;

/**
 * SerializationUtil工具类
 * 使用Protostuff实现序列化
 * 
 * Created by Administrator on 2016/8/12.
 */
public class SerializtionUtil {
    private static Map<Class<?>, Schema<?>> cachedSchema = new ConcurrentHashMap<>();
    private static Objenesis objenesis = new ObjenesisStd(true) ;
    private SerializtionUtil() {
    }

    @SuppressWarnings("unchecked")
    private static <T> Schema<T> getSchema(Class<T> cls) {
        Schema<T> schema = (Schema<T>) cachedSchema.get(cls);
        if (schema == null) {
            schema = RuntimeSchema.createFrom(cls) ;
            cachedSchema.put(cls, schema) ;
        }
        return schema ;
    }

    /**
     * 序列化
     * @param obj
     * @param <T>
     * @return
     */
    public static <T> byte[] serialize(T obj) {
        Class<T> cls = (Class<T>) obj.getClass();
        LinkedBuffer buffer = LinkedBuffer.allocate(LinkedBuffer.DEFAULT_BUFFER_SIZE) ;
        try {
            Schema<T> schema = getSchema(cls) ;
            return ProtobufIOUtil.toByteArray(obj,schema,buffer) ;
        } catch (Exception e) {
            throw new IllegalStateException(e.getMessage(), e) ;
        } finally {
            buffer.clear();
        }
    }

    /**
     * 反序列化
     * @param data
     * @param cls
     * @param <T>
     * @return
     */
    public static <T> T deserialize(byte[] data, Class<T> cls) {
        try {
            T message = objenesis.newInstance(cls) ;
            Schema<T> schema = getSchema(cls) ;
            ProtobufIOUtil.mergeFrom(data,message, schema);
            return message ;
        } catch (Exception e) {
            throw new IllegalStateException(e.getMessage(), e) ;
        }
    }
 }
